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From:   Brian Norris <briannorris@chromium.org>
Date:   Thu, 29 Oct 2020 11:56:57 -0700
Message-ID: <CA+ASDXONuRUZ_2+-7PtWigp=ZQsS2_guCbmNP30yL2qQZXHThg@mail.gmail.com>
Subject: Re: [PATCH 1/3] mwifiex: disable ps_mode explicitly by default instead
To:     Andy Shevchenko <andy.shevchenko@gmail.com>
Cc:     Tsuchiya Yuto <kitakar@gmail.com>,
        Amitkumar Karwar <amitkarwar@gmail.com>,
        Ganapathi Bhat <ganapathi.bhat@nxp.com>,
        Xinming Hu <huxinming820@gmail.com>,
        Kalle Valo <kvalo@codeaurora.org>,
        "David S. Miller" <davem@davemloft.net>,
        Jakub Kicinski <kuba@kernel.org>,
        linux-wireless <linux-wireless@vger.kernel.org>,
        "<netdev@vger.kernel.org>" <netdev@vger.kernel.org>,
        Linux Kernel <linux-kernel@vger.kernel.org>,
        Maximilian Luz <luzmaximilian@gmail.com>,
        Andy Shevchenko <andriy.shevchenko@intel.com>, verdre@v0yd.nl
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On Thu, Oct 29, 2020 at 11:37 AM Andy Shevchenko
<andy.shevchenko@gmail.com> wrote:
> And this feeling (that it's a FW issue) what I have. But the problem
> here, that Marvell didn't fix and probably won't fix their FW...

Sure, I wouldn't hold your breath. So some of these tactics (disabling
PS, etc.) may be valid, but you have to do them smartly, acknowledging
that there are other (more stable) firmwares and chips in use for this
same driver.

> Just wondering if Google (and MS in their turn) use different
> firmwares to what we have available in Linux.

No clue about MS. But Chrom{e,ium} OS generally publishes all this
stuff where possible. You can see what we use here:

https://chromium.googlesource.com/chromiumos/third_party/linux-firmware/+/HEAD/mrvl/
https://chromium.googlesource.com/chromiumos/third_party/marvell/+/HEAD/

We try to stay somewhat in sync / parallel with "upstream"
linux-firmware, and strongly encourage vendors to send the same
binaries upstream when they hand them to us, but there are exceptions
and oversights (e.g., old products might have used a different
firmware branch).

Notably, I'll repeat: we (Chrome OS) don't actually support the PCIe
variant of 8897, so the report in question ("PCIe-88W8897") has no
equivalent in a supported Chrome OS system (even if there are binaries
in the links above, we don't use them). I would not be surprised if
there are an enormous number of firmware bugs there, as there were
initially for PCIe-88W8997 (which we do support).

Brian